Contrast agents are provided by manufacturers in numerous concentrations in sterilized containers (such as glass bottles or plastic packages) ranging incrementally in size from 20 ml to 200 ml. These containers are generally designed for a single use in which once a container is opened for a patient, then it is used for that patient only. The contrast is, generally, aspirated from such containers via a syringe pump used to inject the contrast agent, and any contrast agent remaining in the container is discarded to prevent infection with potentially contaminated contrast. The medical staff is faced with the task of choosing an appropriately sized contrast container to assure an adequate injection while minimizing discarded contrast. Time consuming procedures are required to reload the syringe if more contrast is required than originally calculated, and expensive waste results if only a portion of a filled syringe is injected. The inventory of contrast containers required under the current system increases costs and regulatory burdens throughout the contrast media supplier-consumer chain.